DE7210316U - VIEWING DEVICE - Google Patents

Description

PATENTANWÄLTE DR.-ING. WOLFF, H. BARTELS DR. BRANDES, DR.-ING. HELD Diol.-Phys. Wolff ] _(ϊ Ι;! |! 5.ϋ.? 1 ²

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Our reference: 123 526/852033 kdk

Eastman Kodak Company, Rochester, New York State, United States of America

Viewing device

PATENTANWÄLTE DR.-ING. WOLFF, H.BARTELS, DR. BRANDES, DR.-ING. HERO Dipl.-Phys. Wolff

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The invention relates to a viewing device for projecting an image arranged on a photographic information carrier on a screen, with a light source for Illuminating the image located on the information carrier with a transport device for moving the information carrier with respect to an optical axis, which is aligned like a viewing opening to the screen, and with at least one reflective element.

On the. See the field of projection equipment, there is always the difficulty of projecting an image onto the front of a reflected-light screen or onto the back of a rear projection screen in such a way that the image projected in this way has optimum quality and optimum contrast. In addition, a number of proposals have been made for the design of a B ⁴ screen in which ambient light which may be incident on the viewing surface of the screen is essentially eliminated, so that an image with improved quality and improved contrast can be achieved. Parabelling of the projected image has also been proposed. This is done, for example, by arranging a suitable filter in the optical system, usually in conjunction with a condenser lens system. Such a filter arrangement, however, reduces the image intensity or brilliance in such a way that the image contrast is considerably reduced. Such a filter arrangement also does not allow any control of the ambient light impinging on the viewing surface of the screen. If a reflected-light screen is used in a viewing device, the housing is provided with a viewing opening or an open side through which the

Ι · Image projected on the screen can be viewed.

p. However, such a configuration does not lead to just one

adverse accumulation of dust and dirt on the screen, but also on springs of the reflective body, which are arranged inside the housing and a part of the projection optical system. Another disadvantage of the known devices is that they only permit the evaluation and viewing of photographic information carriers of the same type. In the However, photographic information carriers in the form of microfilm cards, microfilm rolls, film strips, Evaluate transparency images, etc.

The invention is based on the object of a viewing device for projecting an image arranged on a photographic information carrier onto a screen to create that is particularly functional and can be used in a variety of ways.

This object is aisgehend dissolved by a viewing device of the type mentioned according to the invention in C that the viewing device comprises a base unit and a housing unit, wherein the base unit, the light source and the transport device for the information carrier and wherein the housing unit separable from the base unit and contains the viewing opening, the reflective element and the screen, and that the base unit and the housing unit each have connecting parts for their mutual connection to the viewing device. Due to the modular structure according to the invention of the viewing device, its housing unit and its base unit each contain a part of a complete optical system

• · <· Ii

and against differently constructed housing or base units are interchangeable, a structure that is particularly important for such devices is achieved “An essential one The advantage of the modular assembly of the viewing device according to the invention, however, is primarily that through the easy interchangeability of appropriately constructed units the most diverse photographic information carriers, such as microfilm cards, microfilm rolls, film strips, transparencies or the like are evaluated can be when a base unit provided, for example, for microfilm cards against one, for example, for a Filmstrip provided base unit is replaced. Such an exchange, which demonstrates the versatility of the the viewing device according to the invention is improved in a decisive way, can be carried out in a short time and in an expedient manner carry out.

The connecting parts can either have two spatially separate, mutually parallel uprights, which of one Stand off bottom surface of the housing unit at an angle, the base unit means for receiving and for Has securing the stand for a connection of the base unit with the housing unit, or in the case of an advantageous modified embodiment a frame, preferably in the form of a slipway! have which by angled edges of each side wall of the base unit is formed and for detecting and supporting a corresponding angled surface of the housing unit is used. In the last-mentioned case in particular, the housing unit during the assembly of the viewing device according to the invention by d <<? Contour of the side walls of the Base unit aligned and centered in a particularly useful manner.

The photographic information carrier is preferably a microfilm card on which in X-Y coordinates a plurality of images are arranged, the transport device for aligning a selected image of the Microfilm card for the optical axis in the X and Y directions is arranged movably in the base unit. At the information carrier however, it can also be a film strip on which several images are drawn in the longitudinal direction are arranged and wherein the transport device for the film strip is arranged on a plate of the base unit and is used to align a selected image with respect to the optical axis.

In a further, particularly advantageous embodiment According to the invention it is provided that the housing unit is a hollow, cylindrical one projecting from its bottom surface Has sleeve which is aligned substantially to the projection part when the housing unit on the its bottom surface is arranged matching side walls of the base unit, and that between the projection part and the sleeve, when the housing unit and the base unit are connected to each other, means for sealing the Housing unit against the ingress of dust and dirt is provided from the housing environment. On the one hand, the cylindrical sleeve takes on the task of aligning the in the housing unit located part of the optical system to the projection part located in the base unit and the lighting unit and on the other hand, in connection with the means for effectively sealing the housing unit, which is preferably designed as a Guwmiunteriagsscheibe, an effective seal of the housing unit against penetration of dust and dirt from the housing area. A full

Komroene sealing of the housing unit can be achieved, if this has a filter arranged between the viewing opening and the screen. Through appropriate The selection of the filter can be the Cont. Branch u: id the image brightness or luminance of the projected image can be significantly improved.

7210318

The invention is based on the following description

of exemplary embodiments illustrated in the drawings iai individually explained.

ψ It show:

I Fig. 1 is a side view of an orsten embodiment

game of a viewing device according to the invention, the housing unit is shown in section;

FIG. 2 is a front view of the base unit of the viewing device according to the invention shown in FIG.

3 shows a vertical section along the line III - III in FIG. 2;

Fig. 4 is a vertical section through part of the % housing unit, in which a reflector is arranged fishing, which effectively the I condenser lens for illuminating a photo

f forms graphic information carrier;

Fig. 5 is a vertical section through part of a

Base unit of a modified viewing device, in which a condenser lens together, men with a projection lamp with low

r wattage is applied, which immediately

ν is aligned with the condenser objective;

FIG. 6 shows a side view of an ab-5s similar to FIG. 1 converted viewing device according to the invention

[dung, the housing unit of which is shown in section

I represents is;

721Q316-MU3

Pig. 7 is a partial perspective view of the connection between the housing unit and the base unit

/ serving connecting parts:

8 shows a section along the line VIII - VIII in

Fig. 3, wherein a transport device for the Information carrier is shown, which has images arranged in X and Y coordinates, j that is transported to the opti

cal axis of the projection system can be aligned are;

9 is a front view of a modified embodiment of a transport device for the Information carrier which can be used in the viewing device according to FIG. 1 or 6, and

10 and 11 are schematic representations of the relative positions of the projection lens and the screen of the viewing device for growth the rejection of ambient light by the screen.

Reference is first made to the exemplary embodiment of a viewing device shown in FIGS. 1 to 3. This viewing device 25 has a base unit 30 and a housing unit 10, which is on the base unit is mounted. In this embodiment, the base unit 30 comprises a lighting part 31 and one for Handling of an information carrier serving projection part 26.

The lighting part 31 is provided with ventilation slots 33 provided that the circulation of air around a project

721031 € -β, 11.73

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Allow tion lamp 11, which is arranged on a stand 27, which in turn is attached to the bottom 28 of the lighting part 31 »A condenser lens 12 is arranged in the Eeleuohtungteil 31, with a mirror 12 * arranged between the condenser lenses in the manner shown in FIG is. The side walls 55 of the lighting part 31 extend from a front wall part 54 and are 4 "*
Assembled state of the same extent as sixth / ί Fig. 7) of the projection part 26 used for handling the information carrier. Each of the side walls 29 and 55 is provided with a protruding projection 57 and 56 (see. Fig. 7) _# whose purpose is below is described in more detail.

The one intended for handling the information carrier
Projection part 26 has a plate 58, which in the
in Fig. 3 manner shown from a front wall part. The projection objective designated by the reference number 13 is in a carrier fastened on the plate 58
23 arranged. The projection lens itself can be moved axially in the carrier 23 by means of an axis 37 and a lever 32 mounted in the front wall part 59. The axis 37 carries
'- an eccentric pin 36, which is used to move the projection lens 13 in the axial direction with respect to its
Carrier rests against the projection lens; so that the image projected on a screen 16 can be focused.

Spatially separate rails 46 and 49 are either integrally connected to the underside of the plate 58 or mounted on it and serve for the displaceable mounting of a plate 38, which is labeled with a
18 designated carrier is connected, in turn the

¹ I.

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Iitformationstrftger, such as a microfilm card 34 also known under the name "microfiche" carries. The plate 38 has two spatially separated, upwardly projecting extensions 47 and 46 * which have corresponding projections and grooves for engaging in the rails 46 and 49 for a sliding movement. A button 19 is rotatably mounted in the front wall part 63 of the plate 38 and carries a roller 21 connected to it in one piece, which rests on the microfilm card 34 and projects it in any direction in the X direction, which according to FIG. 3 is perpendicular to the plane of the drawing can move back. A pulley 41 is rotatably mounted on the plate 38. A cable 42 is wound one and a half times around a narrow roller 40 which is arranged on an axle 39 which carries a button 20 at each end in the manner shown in FIG. The cable 42 contacts the pulley 41 and v with His beiaen ends to the Kiifc * x reference count 4 "ΐ designated site on a spring element 4 <attached which uxv arranged in a sleeve 45. There is attached at its upper end to this This arrangement holds the cable 42 taut. The spring element 44 also allows the cable 42 to slip with respect to the roller 40 if the knob 20 is turned more than is necessary to move the plate 38 into one of the two extreme positions in the Y- Movement of the microfilm card 34 in the X and Y directions is accomplished by buttons 19 and 20. Movement of the microfilm card 34 in the X and Y directions to accommodate any of those on the microfilm card Images can be aligned with the optical axis 22 and projected onto the screen 16, can also be carried out in other ways that are known to the person skilled in the art.

- 10 -

The shape of the housing unit 10 can best be seen in FIG. 1, according to which the base 60 meets the side walls 29 of the projection part provided for handling the microfilm card 26 touched :. The housing unit 10 has a cylindrical sleeve 61 which has an image entry opening 62 in the housing unit. The sleeve 61 extends from the base 60 in the direction of the carrier 23 for the projection lens 13. The length of the sleeve 61 is selected in such a way that a soft rubber washer 14 is on the carrier 23 for the projection lens 13 when the housing unit 10 is connected to the base unit 30, i.e. the projection part 26 and the lighting part 31, slightly in one Way is compressed so that a seal is created between them, which prevents dust and dirt from entering the Housing unit 10 prevented from the housing environment.

That image of the micro film card which is used for the optical Axis 22 is aligned and is projected through the image entry opening 62 into the housing unit 10, is by means of a mirror 15 is reflected onto the front side of the incident light screen 16. One in the front wall part 63 ('The viewing opening 35 provided in the housing unit 10 creates the possibility for an observer to see the the front of the screen 16 can view the projected image. The incident light screen 16 is preferably one known from U £> -PS 3 408 132 Screen in which the brightness of the image increases due to a special structure of the screen surface can be achieved to about 40 times.

The housing unit 10 has side walls 86 and a ^r Declcelteil 87, which together with the bottom 60 over a

· ■ ^: ·· ■■

The filter 17 protrudes and ends in the front wall part 63. the Sections of the bottom 60, the front wall part 63, the Side walls 86 and of the cover part 87, which protrude beyond the filter 17, form a shield 88 in the form of a hood. The inner surfaces of the wall parts forming the housing unit 10 including the inner surfaces of the shield 88 are preferably blackened, so that light is reduced and Scattered light are absorbed.

The filter shown in Fig. 1 is flat and in the housing unit 10 between the viewing opening 35 and the incident light screen 16 are arranged. That Image of the microfilm card 34, which is directed to the optical axis 22 is aligned, is on the reflected light screen 16 over the projection lens 13, the image entrance opening 62 and the mirror 15 are projected.

The filter 17 comprises one made by the Eastman Kodak Company, Rochester, New York, United States of America blue filter element labeled "80 C", which combines with a neutral density filter element whose density factor depends on the light source and the increase in brightness of the screen. The filter elements are to achieve the required mechanical strength and stability on a carrier film made of transparent Acetate arranged or summarized as integral parts of a suitably composed plastic film. Such a light filter structure corrects the color temperature of the light source and thereby improves both the Image contrast as well as the luminance of the image. One from the Eastman Kodak Company, Rochester, New York, United United States-made blue filter element with

7210318-Mtn

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the designation "80 B" can also be used. For the filter elements with the designations "80 B" and "80 C" it is a Wcatten filter, which belongs to the group of light compensation filters. The characteristics of this Filters are, for example, the reference "Applied Optics and Optical Engineering", volume. 1 published by R. Kingslake, Academic Press, New York and London, see pages 119 to 124, in particular Tables V and VI. In practice, the density factor des is sufficient neutral density filter from about 0.4 to 0. In the latter Trap, no density filter is required due to the small amount of light emitted. For a specific light source, which is operated below its nominal voltage, the type of light compensation filter and the density factor of the neutral density filter is chosen such that the image reflected from the screen has an optimal luminance possesses when viewed by the observer. If the light source is an incandescent lamp, such as an automobile lamp with a nominal voltage of 12.8 volts and this lamp is operated at this nominal voltage, then the life of the lamp is approximately 100 hours. Will the same lamp at a diminished Voltage of approximately 11.2 volts, then the filament produces a color temperature of approximately 2800 Kelvin / the life of this lamp increases to about 500 hours. When using the aforementioned Wratten-F liter element s labeled "80 C" can be dj.e color temperature the lamp in an effective manner up to the color temperature of a light source with 4000 ° Kelvin based on the black body can be raised. If the brightness of the screen increases or if the emitted If the amount of light and / or the light intensity of the lens is increased, a neutral density filter element is required,

- 13 -

its density factor as well, to about 0.4 or more increases depending on the other factors. The luminance of the image should be in clear B-ranges for a sufficient

2 take a consideration of approximately 1290 candelas per τα .

At the extra viewing angles of approximately - 7 1/2 in the horizontal and approximately ± 2 1/4 ° in the vertical direction, which is determined by the viewing opening 35 or

^ are limited, the effective cellar increment is about 30 times that of a typical screen. If ideal light distribution could be achieved then let achieve even higher growth yourself. The theoretical increase is at these angles and at ideal 159 times the light distribution. The curvature of the screen is chosen so that at a viewing distance of Approximately 53 cm across the entire screen no deficiency in the uniformity of brightness, such as intense light spots, was observed is. The radius of curvature of the screen is approximately 44 cm, while the distance between the lens and the screen is approximately 37 cm. Such an image

V screen with large increase in brightness is for the desired Light output responsible, although a projection lamp with low wattage and a filter are used, the latter optimizing the luminance of the image reflected from the screen when it passes through the viewing opening is observed.

When using a projection lamp with a low wattage, for example a lamp with 12 watts, in the Use of the in Fic. 3 shown condenser lens 12 including the mirror 12 ·, when using a Projection lens with a light intensity of f / 3.5,

7110318

I - 14 -

I when using the reflected-light monitor described above

I 16 and without the use of a filter in such a

^? System has been found that an image brightness or

I Luminance of 12,900 candelas per m with the film stage open

I is achievable. i.e. if there is no information carrier in the

% System is located. This is quite open to the observer-

I obviously way too bright. A comparison shows what

a white sheet of paper in a well-lit office has an image brightness of around 1080 to 1290 candelas

ever m can reflect. It is for these reasons that the filter 17, which serves a number of useful purposes.

In Fig. 4, a much simpler lighting system is shown. In this arrangement, the condenser objective 12 and the mirror 12 'replaced by an ellipsoidal mirror i made of pressed aluminum, its reflective

!; Surface must be manufactured with extreme accuracy.

In this embodiment, the projection lamp be replaced by a smaller lamp 66 and a separate reflector 67.

In Fig. 5, a small lamp 68, for example the bulb of a flashlight, is shown, which in series is arranged with the lenses forming the condenser objective 12. With such an arrangement, the lamp 68 can with

j are fed with a voltage of approximately 4 1/2 volts,

which is supplied by 3 C-shaped dry cells which are arranged inside the lighting part 31. A

The reflector 69 serves the same purpose as the reflector 67 shown in FIG. 4. These reflectors 67 and 69

k almost double that which occurs on the incident light screen 16

f 721081 «-

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fende light.

Reference is now made to the modified embodiment of a viewing device shown in FIG. its housing unit 10 'in comparison to that shown in FIG Housing unit 10 is made shorter. This is caused by the fact that the projection lens 13 and the Condenser objective 12 together with the transport device for the microfilm card in the manner shown in FIG moved to the left. This change requires a corresponding change in the angle of the mirror 15, as a result of which the angle measured to the mean normal increases from 11 ° (see FIG. 1) to 14 ° (see FIG. 6). The magnification of the angle measured relative to the center line shortens the distance between the incident light screen 16 and the Mirror 15, while by the interaction of the adjustment of the mirror 15 and the optical axis 22 of the condenser lens 12 and the projection lens 13 ensures that the filter 17 can also be moved to the left. That The filter is curved at least at its upper end so that the shield 88 can be made shorter can. The shape and size of the shield 88 and thus the dark zone 51 and the property of the shield 88 on the filter effectively removes ambient light To keep the observation area of the observer away, depend on the curvature of the filter 17. With the aforementioned Changes to the housing unit can also enlarge the viewing opening 35 in a manner which is related to the position of the eyes of the observer in a vertical direction creates more freedom of movement. An enlargement of the Mean normal measured angle by 3 improves the rejection of ambient light because the brightest sections

- 16 -

the ambient light reflected by the screen 6 ° further be deflected away from the viewing opening 35, whereby it for the most part through the blackened inner walls of the housing unit 10 * is absorbed.

10 and 11 show, on a relatively small scale, the respective position of the incident light screen 16, the projection lens 13 and the film plane F with respect to one another; the mirror 15 is not shown. It is generally known that the lines which run parallel on the photographic information carrier when a line N-2 is laid through the main point N of the projection lens 13 parallel to the film plane F and is extended to the point of intersection with a line SI which is in the plane of the incident light screen 16 is, form images on this screen which seem to meet at the same distant intersection point ZXk. In Flg. 10 the film plane is shown running at right angles to the connecting line between S and N. This is a principle illustration of the exemplary embodiment shown in FIG. 1, the lines N-2 and SI enclosing an angle of 11 ° and intersecting one another at a point which is at a large distance from the screen. The amount of trapezoidal distortion of the image projected on the screen, which this angle embodies, is less than 3 ° inclination of the edges with respect to the vertical center line of the screen or / an image approximately 14 mm narrower with respect to the top of an approximately 15 cm high screen the width of the image at the bottom of such a screen. This amount of trapezoidal distortion of the projected image can be considered acceptable and enables the projection lens 13 to be used on the projection axis. At an off-axis angle of 14,

I ι ι

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which is shown in Fig. 11, the film plane extends at an angle of 87 ° to the connecting line S-N, so that the lines N-2 and S-I again enclose an angle of ii °. The amount of trapezoidal distortion of the projected The picture does not change in any way. However, the correct focal plane requires that the lens has a half-angle coverage that is approximately 2 ° greater.

When shortening the housing unit 10 ', the: for Handling of the microfilm card serving projection part 26 and the Belsuchtungteil 31 in the manner shown in FIG can be combined into a single unit 70, so that the housing unit 10 'and the unit 70 can be separated from one another are. In this case, the side walls 71 of the unit are formed continuously, while its edges 73, on which the housing unit 10 * is arranged, in its course the contour of the bottom 60 of the housing unit are adapted. In such an arrangement, the plate 38 provided as a carrier for the microfilm card is approximately the same as that described above Kind of movably arranged so that the microfilm card 34 is movable in both the X and Y directions, the movement in one direction being more suitable either by turning Knobs or by turning a single knob while holding the plate for one movement in the other Direction can be shifted by hand. As in the embodiment described above, the housing unit 10 ' a sleeve 61 which contacts the washer 14 of the carrier and thereby a seal between the housing unit 10 »and the unit 70 causes.

With regard to the viewing device shown in FIG. 1 or 6 the plate 38, which carries the microfilm card, can be replaced by a plate 75, which is shown in FIG.

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provided way two spatially separated spindles 76 and 77 carries. When using a suitable film carrier 78 may be a strip of film 79 having a width of 8, 16 or 35 mm with respect to the optical axis 22 of the viewer be moved. In this example, the film strip 79 carried by a spool 80 which is rotatably mounted on the spindle 76. The filmstrip will be under a Guide roller 81 through, under the film carrier 78 and around another guide roller 82 to form a spool 83 the spindle 77 out. A suitable button or a drive device can be one or both spindles 76 and 77 so that the film strip 79 with respect to an opening 84 of the plate 75 and an opening 85 of the film, stage 78 is movable. Such a transport device for the photographic information carrier can be in in a simple manner to the base unit 30 of the one shown in FIG Viewing device or to the unit 7O of the viewing device shown in FIG. 6 adapt.

The device for connecting the housing unit 10 to the base unit 30, which includes the projection part 26 and the lighting part 31 includes, to the viewing device, has two spatially separated stands 90, which on The bottom 60 of the housing unit 10 is attached or formed in one piece with it. The uprights 90 are spaced apart arranged from each other and connected to one another by means of a plate 91, which in the assembled state of the two units forms an extension and continuation of the bottom 28 of the lighting part 31. The protruding from each side wall 55 Approach 56 (see. Fig. 7) engages the surface 93 of the plate 91 in the manner shown in Fig. 3, the Adjacent side walls to the edges of this plate. Suitable

- 13

Tension the screws 94. Lighting part 31 with the stands 90 so that the lugs 56 actually rest on the plate 91. The approaches 57 protruding from the side walls 29 also touch the surface 93 of the plate 91, in the assembled state the side walls 29 and 55 are from same extent, their edges 95 and 96 include an opening through which the plate 38 for the microfilm card is movable. The edge 97 of the side wall 29 is aligned with the end of the plate 91 while to avoid it a lateral movement of the side walls 29 an extension 99 engages in a recess 100. Also the over an edge 101 protruding portion of the protruding lug 56 contacts the side wall 29 to thereby any To prevent lateral movement of the side walls 55. The projection part 26 is in its position by means of screws 102, which connect it to a protruding extension 103, and held by screws 104, which the plate 58 with connect a protruding extension 106.

In the exemplary embodiment shown in FIG The viewing device becomes the device for securing and storing the housing unit through the course of the edges of the side walls 71 of the unit 70 is determined. The various angled edges 73-1, 73-2 and 73-3 of each side wall 71 form a frame in which the housing unit 10 'can be arranged, the edges in their course to the contour of the bottom 60 and a rear wall 74 of the housing unit 10 * are adapted lugs 107 are provided on the side walls 71 and on the bottom 60 so that the housing unit 10 'and the unit 70 using suitable connecting means, for example screws 108, can be firmly connected to each other * Both in the case of the viewing device according to FIG

- 20 -

• ·

The type of connection as well as in the case of the type of connection provided in the case of the viewing device according to FIG. 6 is the cylindrical Sleeve 61 brought into contact with rubber washer 14, so that the necessary seal between the housing unit 10 or the housing unit 10 'and the base unit 30, i. H. the projection part 26 or the unit 70 is produced.

From the preceding description it follows that due to the modular structure of the viewing devices described above different types of base units and transport devices for the information carrier with each other can be combined and / or exchanged and assembled in a simple manner to form a complete unit. Such a modular structure also creates the possibility that most of them are using the viewing device available photographic information carriers, such as microfilm rolls, cassettes, transparencies, etc. can be evaluated. In any case, it is possible to use light sources with a low wattage achieve high image contrast, so the use of fans or glass plates to control the heat and consequently the Flatness of the photographic information carrier is not necessary. As a result of the use of light sources with low Wattage can also be the voltage source for example from the available flashlight batteries, 12-volt car batteries or 110-volt light voltage sources be selected »When using a light source with a low wattage, the viewing device can, because it is completely portable, can be taken anywhere and is completely independent of any local voltage source.

niei18-iifi.fi

Claims (1)

- 21 - • · · »» it • · · III * · · * I III • · · I I. I. RETENTION CLAIMS 1. Viewing device for projecting one on a photographic one Information carrier arranged image on a screen, with a light source for illuminating of the image located on the information carrier, with a transport device for moving the information carrier with respect to an optical axis which is aligned like a viewing opening to the screen, and with at least one reflective element, characterized in that that the viewing device (25) has a base unit (30) and a housing unit (10, 10), wherein the base unit the light source (11,31,66,68) and the transport device (18 to 21, 38 to 49) for the Contains information carrier (34) and wherein the housing unit is separable from the base unit and the viewing opening (35), the reflective element (15) and the screen (16) contains, and that the base unit and the housing unit for their mutual connection to the viewing device each have connecting parts (23,61,73,91) 2. Viewing device according to claim 1, characterized in that the connecting parts have two spatially separate, mutually parallel uprights (91) which protrude from a bottom surface (60) of the housing unit (10,1O ¹ ) at an angle, and that the base unit (30) has means (91, 99) for receiving and securing the stands for connecting the base unit to the housing unit. I - 22 - 3. Viewing device according to claim 1 or 2, characterized in that the connecting ^{parts have a frame, 1} I which by angled edges (73-1,73-2,73-3) of each / side wall (71) of the base unit (30, 7O) is formed and is used to grasp and support a correspondingly angled surface (60) of the housing unit (10 ¹ ). j 4. Viewing device according to one of claims 1 to 3, characterized I characterized that the base unit (30) eii..en lighting ^ / device part (31) and a projection part (13,26), which is between the housing unit (10,10 *) and the loading ! lighting part arranged and with connecting elements (23, 58,59,103,106) for connecting the housing unit with the loading b leuchtungsteil and the projection part is provided. I 5- viewing device according to any one of claims 1 to 4, characterized i that it is in the photographic infor- ^; mationträger is a microfilm card (34) is on -, which has several images arranged in XY coordinates, ? and that the transport device (18 to 21, 38 to 49) to Alignment of a selected image of the microfilm card I t to the optical axis (22) in the X and Y directions in the * base unit (30) is movably arranged. i 6. Viewing device according to one of claims 1 to 4, characterized characterized in that the information carrier is' a film strip (79) on which in the longitudinal direction ; several pictures are arranged, and that the transport I set up (76 to 78, 80 to 83) for the film strip a plate (75) of the base unit (30) is arranged I and to align a selected image with respect to the te optical axis (22) is used. - 23 - • β • * ■ ■■. s 7. Viewing device according to one of claims 4 to 6, characterized in that the housing unit (10, 10 ') has a hollow, cylindrical sleeve (61) which protrudes from its bottom surface (60) and which essentially faces the projection part (26) is aligned when the housing unit is arranged on the side walls (29 or 71) of the base unit (30,70) adapted to its bottom surface , and that between the projection part and the sleeve, when the housing unit and the base unit are connected to one another, a device (14) is provided for sealing the housing unit against the ingress of dust and dirt from the surroundings of the housing. 8. Viewing device according to one of claims 1 to 7, characterized in that the housing unit (10,1O ¹ ) is arranged between the viewing opening and the screen, the housing sealing filter (17). having. 714MlI-m